Pre-operative prevalence of asymptomatic carriers of COVID-19 in hospitals in Catalonia during the first wave after the resumption of surgical activity. / Prevalencia preoperatoria de portadores asintomáticos de COVID-19 en hospitales de Cataluña durante la primera ola tras el reinicio de la actividad quirúrgica.

INTRODUCTION: The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity. METHODS: Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2. RESULTS: A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72hours prior to surgery. The prevalence of asymptomatic carriers was 0.7% (95%CI: 0.6% - 0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (95%CI: 1.1%-3.2%)]. CONCLUSIONS: The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period.